what kind of light to use?

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ilovemydragongoby

Aquarium Advice FINatic
Joined
Jun 14, 2010
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so i'm planning on doing a high light planted tank. my tank is 30x12.5x16 (L x W x H) what kind of light do i need to get for best results. I havent done much research for plants yet but after having great results in my 80gal low lites i want to try something else.

Help Please!
 
The 30" length can be tricky. Avoid 30" bulb fixtures. There aren't many manufacturers that make 30" bulbs so they can be a pain to find.

Go with 24" T5HO bulbs. There are 30" fixtures that stagger these bulbs for better tank coverage. Otherwise, just raise the fixture above the tank to eliminate dark spots.

If you really want to go crazy, check out metal halides.
 
The other possiblity is Power Compact Flourescents. These are basically T5s bent into a U. They are thus available in various lengths and wattages. They are also reasonably priced if bought from a lighting supply rather than an aquarium store.
 
You can also build your own canopy and get some waterproof endcaps, standoffs, reflectors, bulbs and a ballast and make your own lighting. I'd go with a staggered T5HO bulb also, or T8s at a minimum.

Keep in mind that the old WPG rule was for T12s.

http://www.aquariumadvice.com/forums/f24/updating-the-wpg-rule-theory-69964.html

T8s have about 40% more lumens per watt than T12 and T5 about 67% more. "Roughly". Each product has different characteristics, keep that in mind.

Here's a quick lookup comparison, from bulbs.com (by no mean aquarium grade bulbs, but you get the general idea)

Your standard 20W 24" T12 has about 1000 lumens or 50 lumens/watt.

T8s run about 1200 lumens for 17W or 70.5 lumens/watt

Standard T5s run about 700 lumens for 13W or 54 lumens/watt

T5 HOs run about 2000 lumens for 24W or 83 lumens/watt

So if you have a 29 gallon (is that right?) then running 2 T5HOs will give you (24W x 2) x 1.67 = 80 W equivalent, div by 29 Gal = 2.75 WPG

Or, you have 30*12.5 = 375 sq in of horizontal surface area and 4000 lumens for 2x24 T5HO, 4000/375 = 10.67 lumens/sq in which would be "medium" lighting according to this table in that thread above

http://www.aquariumadvice.com/forums/f24/updating-the-wpg-rule-theory-69964.html#post595403

So really the only way to get a truly "high" light tank I would think would be to go with 3 or even 4 T5HOs. The reflectors might throw those #s off however, because the TEK II manufacturer say they get 200% more useable lumens from their reflector.

Food for thought. Plus I'm really bored this morning. Can you tell?
 
thanks for the help guys, i'll have to shop around for something good.

my tank actually measures out to about 33.5 gals when i do an aquarium calculator online, and ive tried a couple different ones to make sure, i get the same result from everyone. (i bought the tank used, he told me it was a 20gal lol)
 
so someone from my city's fish forum finally replied to my add. he has a 30" 65W fixture. and it has LED moonlight too. he wants $50 for it. is this a decent price, and would that be enough wattage for what i want to do (High Light Plants)? I'm trying to do the math but my brain isnt working right now lol
 
from what ive searched i think its a coralife compact. i guess ya, similar to what your showing me. i'm still waiting for the guy to msg me back with all the specs on the light. all he told me was it was a 30inch 65 w, with led moonlite.
 
so guys what do you think...i have 2 offers and i dont know which to go with...what light would be better for a medium-high or high light planted tank.

option 1.
30" 65w CF from current usa for $50

or

option 2.
2-18" fixtures he said he's using 18K lights in both of them, (under counter lights, dont know what that means lol) and he used them for a planted tank and the plants grew like crazy.

which would be better?
 
Do you mean 18W lights? Undercounter lights are usually halogen or something like that. I agree with BigJim, they're T5 not T5HO probably, but could be compact fluorescent.
 
i dont know maybe he made a mistake...but he said 18k. but ill go for the compacts then thanks guys.
 
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